Key-changing lock



July 27 1926. 1,594,307'

R. c. L Ewls KEY CHANGING LOCK Filed August '7, 1924 Patented July 27, 1926.

UNITED [STATES PATENTy OFFICE.L

ROLLIN C. LEWIS, .OF STANFORD, CONNECTICUT, ASSIGNOR T O THE ,YALE & TOWNE MANUFACTURING COMPANY, OF STANFORD, CONNECTICUT.

KEY-CHANGING LOCK.

Application led August 7, 1924. Serial No. 730,655.

This vinvention relates .to improvements in changeable combination key 4locks and particularly to such as are adaptable for use with safe deposit boxes, one object of the invention vbeing' to facilitate the operation of changing the setting of the mechanism for operation with the use of Va different key than the one for which Athe mechanism may have been originally set,

A further object is to provide in a lock of the type specified, simple and improved means whereby a key maybe released vfrom the vlock while the bolt is in retracted position, to permit `the insertion of a new change key, and to so construct and arrange such means that the key by which its operation is controlled may Abe inserted through the exposed face of the `lock casing.

With-these yand other objects in View, the invention consists in certain novel features of lconstruction and combinations of parts as hereinafter set forth and pointed out `in the claims.

In the accompanying drawings;

Figure 1 is a view in Velevation of the lock with the cover plate and the change key tumblers and fences and the guard key tumblers removed, and showing positions of the parts when the bolt is projected; y

Figure L2` is a similar view but showing the 'tumbler and vfence assembled;

Figure .3 is ,an elevation showing the bolt in retractedposition, andthe tumbler mechanism `for the change and Aguard keys removed;

Figure 4 is a view similar to Figure 3 with the tumbler and guard mechanisms removed; Figures `5, 6, 7 and 8 are detail views;

Figure 9 is a front view showing the lock casing;`

Figure 10 "is a side view with `the casing partly broken away to expose parts of lthe mechanism, and

.Figure 11 is a view of the releasing key. l'The lock casing 'is `represented at 1 and the cover plate thereof aty 2. A sliding bolt 3 is mounted within the casing 1 and is formed with `a recess 4, with shoulders lin which,fthe cam `5 on va key hub lor plug 6 is cooperable to withdraw or project the bolt, and in order to limit the return or counterclockwise movement of said plug and insure the proper normal 4position of the same, la vfixed stop 7 is provided `to be lengaged bythe cam. The tail portion of the so that `when said `tumbler 22 is moved in 11i bolt `is provided with an elongated slot 8 through which a -post y9 (rigid with the casing) passes, and thus the bolt is Yguided in its reciprocating movements. The tai-l portion of the bolt is also made with a beveled or inclined edge 10 `and with a hole 11 for purposes hereinafter explained. Springpressed change-key l-tumblers 12 are pivotaflly mounted on the post 9 .and in the gatings of these tumblers, `lingers 13 on slidable fences 14 are A,adapted to enter when the tumblers sshal-l vhave been moved by a key to i bring said `gatings into alignment. The fences -are mounted upon the ybolt in rear of the head thereof and are provided with elongated slots 15 for the passage of posts or studs =16 on -said bolt, whereby the fences are guided in their movements. yThe fences are -provided'each with a `plurality of notches 16a to receive va finger 17 on a stationary spline 18, 4all as fully shown and described in patent -to lV. H. "Taylor, March 6th, 1906 and designated by No. 814,385.

The lock is Aequipped -with guard key mechanism and the specific mechanism which may be employed will now be described:

A plurality of spring-pressed guard key tumblers 19'are pivotally mounted on a fixed post or stud -20 and the-gatings of these tumblers (when 'brought into alignment with the use vof a. proper guard key) `are adapted to receive a fence 21 projecting from a guard releasing tumbler 22,--the latter having an open slot y23 at -oneend to receive the post or-studf20and aclosed slot`24 near its other end, 4through Vwhich ylatter slot, a fixed post 25 passes. A spring-pressed vguard latch 26 lies parallel with ythe releasing tumbler 22 and is mounted to 'turn on the post or stud 25. At its lfree end, the guard latch 26 is providedwith `a guard stop 27 which normally is inthe path vof a stop vshoulder 28 on the key plug and prevents such extent of turning of the latteras Ywould eect retraction of the bolt. 4The guard latch-26 is provided between its -ends with a cam slot 29 into .which v a Vpin 8O projecting from the guard releasing tumbler 22 projects, so that whenjsaid tumbler 22 is moved longitudinally in one direction, the latch 26 will be so moved-onits pivotal mounting as to with- 'draw the hook or-stop 27 out of the path of the stop shoulder 28 on the key hub 6, and

mounted on the post or stud 2O and extends rearwardly therefrom, said lever being provided at its free rear end with a lateral beveled lug or projection 32 which is normally disposed behind the beveled rear edge l or the tail or' the bolt 3, and between the lug or projection 32 and a lug or tooth 33 on the guard releasing tumbler 22, a short arm or lever 34.is disposed and pivotally mounted on the post 25. ln order that the arm or lever 34 shall be held rictionally in the position to which it may be moved, a coiled spring 34'a is located on the post 25 and bears against the hub of said arm or lever and against the cover plate of the casing.

An approximately U-shaped lever 35 (or a plurality of such levers) is pivotally mounted on the post 25 and is formed with two arms 36 and 37 separated by a space 38, and

' said lever (or levers) will be normally so disposed by the action of spring means 39, that the arm 36 will be located in the path of the cam on the key hub and prevent said hub and cam from being turned far enough to permit withdrawal of the change key when the bolt is in retracted position. The exposed iace of the casing is provided with a key-hole 40 so located that the head ot' a key 43 inserted through said key-hole will l become disposed in the space 38 which separates the arms 36-37 of lever 35. `When such key, thus inserted, is turned clockwise, its head will engage the arm 37 of lever 35 and so operate said lever as to move the arm 36 thereof, out of the path of the key-hub cam 5, and thus permit the key hub to be turned suiliciently far to permit withdrawal of the change key.

In the operation of unlocking, a guard key 41 is inserted into the hub or plug 6 and turned in clockwise direction. The key, after setting the guard tumblers to align their gatings with the fence 21 will contact at 42 on the guard releasing tumbler 22, and cause the latter to move to the lett, and at the same time, cooperation of the pin 30 on said tumbler with the cam slot 29 in the guard latch 26, will cause the latter to swing on its pivotal mounting so that the h ook or guard stop 27 will be carried out of the path of the stop shoulder 28 on the key-hub or plug 6, thus permitting the free turning of the latter and the change key subsequently inserted. rlhe guard key is then turned back and removed. A change key 42 will now be insertedk into the key hub or plug 6 and turned to retract the bolt, as will be readily understood. As the bolt moves inwardly, its beveled rear end will Contact with the beveled end lug 32 of the lever 31, which in turn will swing the small lever 34 to the right, carrying with it the guard releasing tumbler 22, thus moving the pin in the cam slot 29 of the lever 26 and allowing the latter to spring into position with its guard stop 27 in normal locking position ready to again lock the key plug after it shall have been turned to project the bolt and thus prevent said plug from being turned a second time suliiciently to retract the bolt.

To change thev key setting, the bolt will first be fully retracted and while in this position, releasing key 43 (Fig. 1l) will be inserted through the key hole (the end of the key entering the hole ll in the tail portion ot the bolt 3) and turned clockwise. As the hole 1l forms the inner bearing 'for the key 43, it is evident that the lever 35 cannot be operated except when the bolt is in its fully retracted position. The bit of the key will contact with the arm 37 oit lever 35, causing the latter to so turn on its pivot mounting as to withdraw the arm 36 of said lever from the path of the key plug cam 5, thereby enabling the plug to be turned far enough tor the change key to be withdrawn l'rom the plug. A new change key ot the desired combination may then be inserted and the bolt projected and the lock will then be set to the new key.

Having fully described my invention what l claim as new and desire to secure by Letters-Patent, is

l. In a changeable combinatioirkey lock, the combination with a case, a bolt, and key operated means including a key plug and cam, of a lever pivoted at one end and having two arms forming a space between them, spring means holding said lever in normal position with one of its arms in the path of the cam on the key plug, the other arm o'l' said lever constitutin a key engaging arm, the case having a keyole positioned to permit the insertion ot' a key between the arms of said lever, whereby when said key is turned it will engage the key engaging arm of said lever and swing said lever in a manner to move its other arm out of the path of the key plug cam.

2. ln a changeable combination key lock, the combination with a bolt and key operated means for actuating the same, of a key actuated spring pressed lever operable to normally limit a member of the key operated means, said lever being approximately U-shaped, means normally holding said lever in limiting position, and a key insertable between the arms of said lever and cooperable with one of them to move said lever te releasing position.

3. ln a lock of the character described, the combination of a case, a bolt having a beveled rear end portion, a key plug having a stop shoulder, a bolt operating cam associated with said plug, change key tumbler mechanism, guard .key mechanism including a spring-pressed pivoted guard latch having a stop cooperable with the shoulder on the keyplug, a sliding guard releasing tumbler` having cam connection with said pivoted guard latch and movable in one direction by a guard key to effect withdrawal of the guard latch stop from the path of the shoulder on the key, a lug on said tumbler, a pivo'ted lever having a beveled free end portion to be engaged by the beveled rear end portion of the bolt, a pivoted member between the beveled portion of said lever and the lug on said guard releasing tumbler, guard key tumbler mechanism, and a fence for said guard key tumbler mechanism, carried by said guard releasing tumbler, and a key released lever normally limiting the turning of the key plug by means of a change key.

4. In a changeable combination key lock, the combination with a casing having a key hole in its front face, of a bolt, and key releasing means, said bolt having a bearing for a 'releasing key inserted through the key hole in the front face of the casing, the bear-l ing for the key being so located that it will be positioned to receive the key only when the bolt is in retracted position, whereby the releasing means cannot be operated except when the bolt is in its retracted position.

In testimony whereof, I have signed this specification.

ROLLIN C. LEWIS. 

